JPS62128047A - Tape running device - Google Patents

Abstract

PURPOSE:To set the gain of a tape tension control system most suitably whether the tape running speed is high or low, by feeding back the tape tension to the tape speed. CONSTITUTION:The output of a tape speed voltage generating circuit 21 is obtained as a voltage (a) increased in accordance with the speed of a tape 2, and the output of a gain set voltage generating circuit 22 is obtained as a certain voltage (b) independently of the tape speed. These outputs are added by resistances R1 and R2 and are inputted to the first operational amplifier OP1, and the output of the first operational amplifier OP1 becomes a voltage (c). The second operational amplifier OP2 outputs a voltage (d), and output voltages (c) and (d) are divided by a tape tension detecting resistance 25 and are outputted to a motor driving control means 26. That is, a slider 25A of the tape tension detecting resistance 25 is driven and its position is varied in accordance with the tape tension detected by a tape tension detecting mechanism 24.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a tape running device used in a tape recorder or the like.

[Technical background of the invention and its problems] The tape running device does not apply unnecessary tension to the tape.
In addition, to ensure smooth tape running, tape tension is constantly controlled.

The tension of this tape is controlled by hanging the tape on a tension arm that is biased in one direction by a spring so that the tension arm is always at a constant position. Specifically, tape tension is detected by a tape tension detection means, the signal is amplified by an amplifier circuit, and the reel motor is driven via a motor drive circuit. Furthermore, since the reel motor and the tape tension detection means are considered to be connected via the tape, the entirety forms a closed loop control system.

By the way, the optimal gain of this tape tension control system is when the tape is stopped, when the tape is playing,
It differs depending on when you are running fast winding. Conventionally, the gain has been optimized when the tape running speed is slow.

However, with the above gain setting, there is a risk that the torque will be insufficient during fast winding, which will weaken the tension and cause the tape to snap.On the other hand, if you increase the gain to prevent slipping, the tape may slip. There was a problem in that the gain was too high during slow rotations, such as during stoppage, playback, etc., and the tension arm was damaged.

Furthermore, if the gain is set to be optimal when the tape speed is slow, there is a drawback that the maximum tape speed during fast winding is limited.

[Object of the Invention] The present invention has been made in view of the above circumstances, and provides a tape running device that can optimally set the gain of a tape tension control system regardless of whether the tape running speed is fast or slow. The purpose is to

[Summary of the Invention] To achieve the above object, the present invention provides a tape running device that controls tape tension in each mode of stop mode, playback mode, and fast winding mode, and which detects the tape running speed. tape running speed detecting means for detecting a tape running speed; tape speed voltage generating means for outputting a voltage according to the detected tape running speed; gain voltage dying means for generating a reference voltage for gain setting; and an output of the tape voltage generating means. and an output of the gain setting voltage generating means; a tape tension detection mechanism for detecting tape tension; and an output voltage of the addition means divided according to the tape tension detected by the tape tension detection mechanism. A variable resistor that presses the tape, a motor that drives a reel on which the tape is wound, and a motor drive means that drives and controls the motor to keep the tape tension constant based on the output voltage of the variable resistor. That is.

[Embodiment of the Invention] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

First, an example of a tape recorder to which the present invention is applied will be described as a second example.
This will be explained with reference to the figures. In FIG. 2, there are pick-up reels (T,
A supply reel (abbreviated as SUP reel) 4 for supplying the 3.degree. tape 2 (abbreviated as UP reel) is provided, and each reel 3.degree. 4 is driven by a reel motor 3A, 4A, respectively. Further, between the head section 1 and the T and UP reel 3, a tension arm 5. A tacho roller 6 and a guide roller 7 are provided between the head section 1 and the SUP reel 4, and a guide roller 8.
Capstan 9. A tension arm 10 is provided respectively. The tacho roller 6 is for detecting the running speed of the tape. The capstan 9 drives the tape 2 to keep the running speed of the tape 2 constant during reproduction and recording. The tension arms 5 and 10 are used to detect tape tension. For example, the tension arm 10 is biased in one direction by a tension spring 11, and the tension arm 10 is used to detect tape tension. The tension detecting section 12 detects the position of the tape 2 in response to the displacement.
Learn to detect tension.

Next, an example of the tape running device according to this embodiment will be explained with reference to FIG. Although the reel motors 3A, 4A and the tension arm 5.10 have been described in FIG. 2, only the tension arm 10 and the reel motor 3A will be described below. In the figure, a tape speed detection circuit (tape speed detection means>20 detects the rotation of the tacho roller 5 using an optical encoding method and detects the running speed of the tape 2 based on this. Tape speed voltage generation The circuit 21 outputs a voltage a corresponding to the tape speed detected by the tape speed detection circuit 20.Gain setting voltage generation circuit 2
2 is a variable resistor VR1 to which voltage VCC is applied to one end.
The divided voltage S is output as a reference voltage for setting the gain voltage. The adder circuit 23 adds the output voltage a of the tape speed voltage generating circuit 21 and the output voltage S of the gain setting voltage generating circuit 22 and outputs the sum. For this purpose, the adder circuit 23 connects the first operational amplifier OP
1 and a second operational amplifier OP2, the output voltage of the gain setting voltage generation circuit 22 is inputted to the inverting input terminal of the first operational amplifier OP1 via a resistor R1, and the tape speed voltage generation circuit 21 is inputted via a resistor R2. Further, its non-inverting input terminal is grounded. Therefore, the output voltage a is applied to the inverting input terminal of the first operational amplifier OP1.

The voltage resulting from the addition of b by the resistors R1 and R2 will be input. Note that a feedback resistor R3 is inserted and connected between the inverting input terminal of the first operational amplifier and its output terminal. The output voltage of the first operational amplifier OP1 is input to the inverting input terminal of the second operational amplifier OP2 via a resistor R4, and its non-inverting input terminal is grounded. Further, a feedback resistor R5 is inserted and connected between the inverting input terminal and the output terminal. Note that the output voltage of the first operational amplifier OP1 is a voltage C, and the output voltage of the second operational amplifier OP2 is a voltage d. The tape tension detection mechanism 24 is connected to the tension arm 10. The slider 25 of the VR 2 is configured with a tension spring 11 and is activated in accordance with the tape tension detected by the tape tension detection mechanism 24.
The position of A is changed, and VR2 corresponds to the above-mentioned tape tension detection means 12 in FIG. In addition, the above-mentioned No. 1. Second operational amplifier OP1゜OR
The voltages c and d which are the outputs of the tape tension detection resistor 25
is applied to both ends of the .

The motor driving means 26 receives the voltage f from the slider 25A.
The reel motor 3A is driven and controlled based on the output of the amplifier circuit 26A. still,
Since the reel motor 3A and the tension arm 10 are considered to be connected via a tape, the control system described above forms a servo loop.

The operation of the apparatus configured as described above will be explained with reference to FIGS. 3 and 4.

The output of the tape speed voltage generating circuit 21 is a voltage that increases in accordance with the speed of the tape 2, and is therefore obtained as a voltage a shown in FIG. On the other hand, the gain setting voltage generation circuit 2
The output of No. 2 is obtained as a constant voltage regardless of the tape speed, as shown in FIG. These outputs are connected to the resistor R
1 and R2 and input to the first operational amplifier OP1. Since the first operational amplifier OP1 operates as an inverting amplifier, its output becomes the voltage C shown in FIG. Further, the second operational amplifier OP2 which inputs the output of the first operational amplifier OP1 also outputs the voltage d shown in FIG. 3 by inverting and amplifying the output. These output voltages c and d are divided by the tape tension detection resistor 25 and output to the motor drive control means 26. That is, the slider 25A of the tape tension detection resistor 25 is variably driven in its position in accordance with the large serrations of the tape tension detected by the tape tension detection mechanism 24, and when the tape tension is lower than the reference value. When the tape tension is smaller than the reference value, the tape tension is moved to increase the voltage to be outputted to the motor driving means 26, and when the tape tension is larger than the reference value, the voltage to be outputted to the motor driving means 26 is lowered and outputted. Its position is variable. For example, if the tension arm moves by 80 degrees, the voltage difference between the voltages c and d is ECd.
When ΔEf is the change in voltage at the tape tension detection resistor, ΔEf=ECdXΔθ.

Therefore, the voltage change value Δ at the tape tension detection resistor 25
The large serration of Ef is proportional to the large serration of the voltage ECd, and as a result, the gain of the control system is varied in accordance with the tape speed as shown in FIG. That is, the gain of the control system is set to G1 when tape running is stopped. Gain G2 during regeneration running
．． At the time of fast winding, the gain can be set to G3.

Therefore, the control system is set to the optimum gain regardless of whether the tape running speed is fast or slow, and the tape running speed in early spring is not limited to below a certain value as in the past. Furthermore, since the tape tension is set and controlled to be constant, the tape does not slip and cause running abnormalities.

Note that the present invention is not limited to the above embodiments, and various modifications can be made within the scope of the gist of the present invention. For example, if the capstan rotates together with the tape even in early spring, the tape speed detection means may detect the rotation of the capstan to determine the tape speed. Further, the output voltage (voltage f) of the adding circuit 23 may be applied to one end of the tape tension detection resistor 25 of the variable resistor VR2, and the other end thereof may be grounded.

[Effects of the Invention] As described above, according to the present invention, it is possible to provide a tape running device in which the motor control system can be set to the optimum gain regardless of whether the tape running speed is fast or slow.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a tape running device according to the present invention, FIG. 2 is a schematic explanatory diagram of a tape recorder to which the present invention is applied, and FIG. 3 is a characteristic diagram showing the output voltage of each part in the device of this embodiment. , FIG. 4 is a characteristic diagram showing the relationship between the absolute value of the tape speed and the gain of the control system. 20... Tape speed detection means, 21... Tape speed voltage generation means, 22... Gain setting voltage generation means, 23... Addition means, 24... Tape tension detection structure, 25... variable resistor, 26... motor drive means;

Claims (1)

[Claims] A tape running device that controls tape tension in each of a stop mode, a playback mode, and a fast winding mode,
tape running speed detection means for detecting tape running speed;
tape speed voltage generation means for outputting a voltage according to the detected tape running speed; gain voltage generation means for generating a reference voltage for gain setting; an output of the tape voltage generation means; and an output of the gain setting voltage generation means. a tape tension detection mechanism that detects the tape tension, and a variable resistor that divides the output voltage of the addition means according to the tape tension detected by the tape tension detection mechanism;
A tape running device comprising: a motor that drives a reel on which a tape is wound; and a motor drive means that drives and controls the motor to keep the tape tension constant based on the output voltage of the variable resistor.